It is one of the diseases most common sexually transmitted diseases and is characterized by a latent and recurrent mucocutaneous infection. A major concern regarding maternal infection with HSV during pregnancy is the potential for vertical transmission to the fetus and / or newborn. To reduce vertical transmission, current management guidelines recommend cesarean delivery for women with active HSV lesions perineal or prodromal symptoms at delivery. Several investigations explored the potential use of antiviral acyclovir treatment late in the third trimester of pregnancy to prevent recurrences of HSV at delivery. The results of these investigations suggest that acyclovir, started at 36 weeks gestation, can reduce clinical recurrences and may reduce the need for caesarean sections as a result of active HSV lesions become evident. Valacyclovir is absorbed from the gastrointestinal tract and converted to acyclovir in the hepatic first pass. Bioavailability of this transformation is 3 to 5 times higher than after oral administration of acyclovir, allowing a lower dose interval. Thanks to these favorable attributes, suppressive treatment with valaciclovir in late pregnancy could significantly reduce both the frequency of clinical relapses, as viral lesions at delivery, thereby reducing the need for caesarean sections and the risk of vertical transmission. Currently, however, no published data indicates safety or clinical efficacy of valaciclovir in pregnant women or their babies. Therefore, our objective was to evaluate the efficacy of valaciclovir suppressive therapy initiated 36 weeks of gestation to reduce recurrent genital herpes and to assess preliminarily security in the mother and her child. The medication was suspended after birth, and postpartum mothers received routine care. One of the results was observed that the number of women with clinical recurrences of HSV between the time they started the suppressive treatment and delivery was significantly lower in the group treated with valacyclovir versus placebo. Something important in this study is that there were no significant differences between the valacyclovir and placebo, in mothers and infants, among the variables evaluated to measure the safety of the use of valaciclovir during pregnancy.
Especially, no significant differences between the groups in perinatal outcomes were observed, including birth weight, frequency of hospitalizations in the neonatal intensive care and Apgar score at 5 minutes less than 7. There were also no significant differences regarding the frequency of oligohydramnios, maternal or neonatal renal function. In conclusion we can summarize that the treatment suppressive daily valacyclovir initiated 36 weeks of pregnancy and continuing until delivery in women with documented history of infection recurrent HSV, significantly reduces the number of women with subsequent clinical recurrences of HSV after the start treatment. However, the suppression did not decrease the number of women with viral lesions close to delivery, active HSV lesions at the time of delivery, or the number requiring cesarean active HSV lesions. Although not statistically significant, both the percentage of women with active HSV lesions, as the percentage of women requiring cesarean active lesions was lower in the group treated with valacyclovir group compared to the placebo group. The onset of spontaneous labor is unpredictable, so is also the onset and duration of active genital HSV recurrent. Thus, we believe that an important observation in this study was noted when the entire time between the start of suppressive treatment to 36 weeks to the time of delivery was considered. During this period of approximately 3 weeks, we observed a statistically significant decrease in recurrent HSV lesions active genital among women treated with valaciclovir compared to those treated with placebo. Thus, in the general population of pregnant women with a history of infections recurrent genital HSV, it is reasonable to anticipate that such a reduction in clinical relapses between weeks 36 and childbirth in women receiving suppression with valaciclovir antiviral, could eventually lead a reduction of caesarean sections performed especially for the indication of active HSV lesions at delivery. In future studies, quantitative PCR rather than qualitative detection of the herpes simplex virus, could be useful in determining whether the antiviral suppressive therapy in late pregnancy reduces the viral inoculum that predisposes vertical transmission. Previous studies have investigated the use of suppressive therapy with acyclovir for pregnant women at risk of recurrent HSV infection. The results of our research with valaciclovir are similar to these previous reports where using acyclovir. In addition, physicians who chose to use the antiviral for HSV suppression in late pregnancy, may be encouraged by the improved bioavailability and lower daily dose of valacyclovir compared with acyclovir.
Although valaciclovir is more expensive than acyclovir, a recent cost-effectiveness analysis, it was shown that the suppressive treatment with valaciclovir was economically favorable compared with acyclovir, or no treatment. Another important contribution of this study is to secure information related to the use of valaciclovir in pregnant women. No safety problems in mothers, fetuses or neonates exposed to valacyclovir were identified. Since valacyclovir becomes acyclovir after the first liver passage, the safety profile could also be applied to acyclovir. Some authors might argue that greater experience objectively examined with the use of valaciclovir and / or acyclovir in pregnant before can be established with certainty, the safety of these medications is needed. Despite sharing this position, we are proud of the favorable toxicity profile observed is this study. In addition, no significant adverse effects were reported in previous studies on prophylaxis with acyclovir in late pregnancy. However, in the absence of definitive data regarding safety, universal use of valaciclovir for viral suppression in all women with a history of genital HSV infection, it may not be prudent. Highlights: What question does this work? It shows the experience of the use of valaciclovir to 36 weeks of gestation in women with a history of recurrent genital herpes, reducing the number of subsequent clinical lesions. What adds to what was already known about it? Quantitative PCR rather than qualitative detection of the herpes simplex virus, could be useful in determining whether the antiviral suppressive therapy in late pregnancy reduces the viral inoculum that predisposes vertical transmission.
Further studies to ensure the safety of such treatment are awaited. How does my daily practice? With the introduction of this treatment the number of caesarean sections for active genital herpes lesions, vertical transmission and the number of clinical recurrences of the disease would be reduced.